Dental models and related methods

ABSTRACT

A dental model and related systems and methods, including a first component representing a portion of a patient&#39;s jaw and a second component that is demountably attachable to the first component, and a second component representing a dental structure of interest, such as the remaining portion of a tooth or a dental implant.

CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.15/155,995, filed May 16, 2016, now U.S. Pat. No. 10,299,899, issued May28, 2019, which is a divisional of U.S. patent application Ser. No.13/773,229, filed Feb. 21, 2013, now U.S. Pat. No. 9,375,298, issuedJun. 28, 2016, which claims the benefit of U.S. Provisional PatentApplication No. 61/601,448, filed Feb. 21, 2012, the entire contents ofwhich are incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates generally to dental models, and moreparticularly to dental models having a jaw component and demountablecomponents, such as tooth components and/or implant analogue components,that can be accurately mounted to the jaw component and removed multipletimes. In many embodiments, the dental models disclosed herein can befabricated using additive manufacturing techniques such asstereo-lithography (SLA) and three-dimensional printing.

In the preparation of dental crowns, bridges, and implants, a physicalmodel of the jaw is often used. These jaw models represent the patient'sjaw in the vicinity of the crown(s), bridge(s), or implant(s) beingprepared. Existing approaches for the preparation of these jaw modelshave included milling the jaw model from a solid block of material. Suchmilled jaw models, however, lack desirable features, such as demountableportions that can be accurately positioned when mounted and selectivelyremoved to better facilitate the preparation of the applicable dentalcrown, bridge, and/or implant.

Thus, improved dental models and related methods are desirable,particularly dental models with demountable portions that can berepeatedly accurately mounted and demounted.

SUMMARY OF THE INVENTION

The following presents a simplified summary of some embodiments of theinvention in order to provide a basic understanding of the invention.This summary is not an extensive overview of the invention. It is notintended to identify key/critical elements of the invention or todelineate the scope of the invention. Its sole purpose is to presentsome embodiments of the invention in a simplified form as a prelude tothe more detailed description that is presented later.

The present invention includes dental models, as well as related systemsand methods, including methods of use and manufacture or fabrication. Inone embodiment, a dental model can include a first component configuredto represent a portion of a patient's jaw and a second component that isdemountably attachable to the first component. The second component canrepresent a dental structure of interest, such as the remaining portionof a tooth or a dental implant. The interface between the first andsecond components includes contact with locally protruding portions onthe first component and/or on the second component. In many embodiments,the first component defines a socket and the second component includes ashaft that is received by the socket and interfaces with the socket. Thelocally protruding portions provide increased compliance thataccommodates a design range of interference fit between the first andsecond components.

For a fuller understanding of the nature and advantages of the presentinvention, reference should be made to the ensuing detailed descriptionand accompanying drawings.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view showing a portion of a dental model, inaccordance with many embodiments, that includes a jaw component having asocket with a folded spring, a tooth component having a shaft portionconfigured for insertion into the socket, and a screw that mates withthe shaft.

FIG. 2 shows the dental model of FIG. 1 with the tooth portion of thetooth component shown as semi-transparent to show interface detailsbetween the shaft and the socket, including contact between the foldedspring and the shaft.

FIG. 3 is a cross-sectional view through the socket, the shaft portionof the tooth component, and the folded spring.

FIG. 4 shows the tooth component of the dental model of FIG. 1.

FIG. 5 shows a dental model tooth component, in accordance with manyembodiments, that has a rectangular-shaped shaft portion.

FIG. 6 shows a dental model jaw component having a socket configured toreceive the tooth component of FIG. 5, in accordance with manyembodiments.

FIG. 7 is an exploded view showing a portion of a dental model, inaccordance with many embodiments, that includes the tooth component ofFIG. 5, the jaw component of FIG. 6, and a screw that mates with thetooth component rectangular-shaped shaft.

FIG. 8 shows a dental model tooth component, in accordance with manyembodiments, that has a generally rectangular-shaped shaft portionhaving a projection portion that may be used to verify insertion depth.

FIG. 9 is a partially exploded view showing a portion of a dental model,in accordance with many embodiments, that includes a jaw componenthaving sockets each with four opposing pairs of compliance features, andtooth components in accordance with the tooth component of FIG. 8.

FIG. 10 is an exploded view showing a portion of a dental model, inaccordance with many embodiments, that includes a jaw component having asocket with sets of cantilevered springs and a tooth component having athree-lobed “tripod” shaft portion.

FIG. 11 shows the socket of the jaw component of FIG. 10.

FIG. 12 shows a socket of a jaw component, in accordance with manyembodiments, configured to receive a three-lobed “tripod” shaft portionof a tooth component such as the tooth component of FIG. 10.

FIG. 13 shows a tooth component, in accordance with many embodiments,having a three-lobed “tripod” shaft portion having a projection portionthat may be used to verify insertion depth.

FIG. 14 shows a dental model component, in accordance with manyembodiments, having a rectangular-shaped shaft having longitudinalcompliance features and with a projection portion that may be used toverify insertion depth.

FIG. 15 shows a dental model component, in accordance with manyembodiments, having a rectangular-shaped shaft having upper and lowertransversely-oriented compliance features and with a projection portionthat may be used to verify insertion depth.

FIG. 16 and FIG. 17 show dental model tooth components, in accordancewith many embodiments, having a rectangular-shaped shaft with hollowupper and lower transversely-oriented compliance features and top stopdetent features.

FIG. 18 is a cross-sectional view through a portion of a dental model,in accordance with many embodiments, that includes a dental modelcomponent and a jaw component, the dental model component having upperand lower transversely-oriented compliance features and a top stopdetent feature, and the jaw component having transversely-orientedsidewall recesses.

FIG. 19 shows a dental model, in accordance with many embodiments, inwhich dental model components having upper and lowertransversely-oriented compliance features, snap-hooks, and bottom stopsurfaces are shown disposed within sockets of a jaw component of thedental model.

FIG. 20 shows a dental model tooth component, in accordance with manyembodiments, that has upper and lower transversely-oriented compliancefeatures, snap-hooks, and bottom stop surfaces.

FIG. 21 shows a dental model component, in accordance with manyembodiments, that has spherical compliance features and is configured tobe received within a socket of a jaw component having stepped sidewalls.

FIG. 22 shows the dental model component of FIG. 21 disposed within asocket of a jaw component having stepped sidewalls, in accordance withmany embodiments.

FIG. 23 shows a dental model component, in accordance with manyembodiments, has spherical compliance features and longitudinalstiffening ribs disposed between the spherical compliance features.

FIG. 24, FIG. 25, and FIG. 26 show dental model implant analogcomponents, in accordance with many embodiments, that have a tab featurethat mates with a corresponding slot in jaw component.

FIG. 27 and FIG. 28 show a dental model jaw component, in accordancewith many embodiments, that has a socket with multiple compliancefeatures and an orientation recess.

FIG. 29, FIG. 30, and FIG. 32 are cross-sectional views showing a dentalmodel implant analog component mounted in a jaw component, in accordancewith many embodiments.

FIG. 31 is a plan view showing a dental model implant analog componentmounted in a jaw component, in accordance with many embodiments.

FIG. 33 shows a dental model implant analog component, in accordancewith many embodiments, that has a flat side surface for use in orientingthe implant analog component relative to a receiving jaw component.

FIG. 34 shows a dental model jaw component, in accordance with manyembodiments, that has a socket with an orientation feature, the socketbeing configured to receive and orient the implant analog component ofFIG. 33.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, various embodiments of the presentinvention will be described. For purposes of explanation, specificconfigurations and details are set forth in order to provide a thoroughunderstanding of the embodiments. However, it will also be apparent toone skilled in the art that the present invention may be practicedwithout the specific details. Furthermore, well-known features may beomitted or simplified in order not to obscure the embodiment beingdescribed.

In the preparation of dental crowns, bridges, and implants, a physicalmodel of the jaw of a patient is often used. The physical model caninclude one or more preparations and/or one or more input analogs, asappropriate for the application. In the past, these models weregenerally milled from a solid block of material.

Advantageously, the dental models disclosed herein can be made usingadditive manufacturing (AM) techniques such as stereolithography (SLA)and 3D printing. The difference in material properties and themanufacturing techniques for dental models that can be made using AMtechniques as compared to traditional milled dental models give rise todifferent requirements and priorities in the design of the models. If,however, a material used to fabricate a dental model as disclosed hereinhas suitable mechanical properties, the dental model may also befabricated using existing milling techniques. Constraints on modelgeometry associated with existing milling techniques, however, may limitthe application of existing milling techniques in the fabrication of thedental models disclosed herein.

The models disclosed herein generally include two or more components.One component represents a portion of a patient's jaw in the vicinity ofthe applicable crown(s), bridge(s), and/or implant(s) to be prepared.This first component is also referred to herein as a jaw component. Oneor more other components are made that are detachably mountable to thejaw component. These one or more other components represent, forexample, each tooth to be crowned and/or each tooth that will support abridge. These one or more other components can be made to match,typically as closely as possible, the corresponding actual dentalgeometry of the patient. For example, for the preparation of a crown, acomponent can represent the geometry of the remaining portion of thetooth to be crowned. Such a component may be referred to herein as a“die” since it can be used as a die to form interfacing portions of thecrown that is prepared. Such a component may also be referred to hereinas a “tooth component”. When dental implants are involved, one or moreof these other components can represent the abutment mounting featuresof the implant(s) as they are located in the patient's jaw. Suchcomponents that represent abutment mounting features of an implant(s)may be referred to herein as an “implant analog component.” Each ofthese other components (e.g., die, tooth component, implant analogcomponent) have features configured to interface with correspondingfeatures of the jaw component such that these other components can berepeatedly mounted to the jaw component so as to be accurately locatedrelative to the tooth and gingiva geometry on the jaw component.

In many embodiments, the jaw component includes at least one socketconfigured to interface with a shaft portion of a die, tooth component,and/or implant analog component. The socket(s) and/or the shaftportion(s) need not be a single continuous shape. For example, the shaftportion can include two separate shaft segments that mate with a socketthat includes two corresponding receptacles. And while in the examplesand embodiments described herein the socket is generally concave and theshaft is generally convex (as illustrated by the choice of terminology),any other suitable configurations in conformance with the couplingapproaches described herein can be used.

To facilitate the fabrication of crowns or bridges, one or more diceand/or one or more tooth analog components may be mounted to anddemounted from the jaw component a number of times. One or more implantanalog components may also be mounted to and demounted from the jawcomponent a number of times, though typically only a few times. It is adesign goal of the dental models disclosed herein that each time thedie, tooth component, and/or implant analog component is inserted thatit reach and remain in a position that accurately represents theposition of the corresponding preparations and/or implants in thepatient's jaw.

Milled dental models are generally made from relatively stiff materials.Properly executed, existing milling techniques can produce a highlyaccurate finished surface. Existing milling techniques, however, may belimited in their ability to produce small features due to cutterdiameter limitations arising from strength, wear, machining time, andcost considerations. In some milled models, the socket and shaft havematching sections taken across insertion direction with the addition ofa very small clearance between these two components. Friction betweenthese components is used to keep these components coupled together in adesired relative position. In such a design, a trade-off is made betweenhaving a relatively small clearance to keep the position accurate andconstant and having a relatively large clearance that may be necessaryso that the die, tooth component, and/or analog can be inserted into thesocket without friction induced jamming that may arise due to tolerancevariations and/or misalignment. Additionally, milled models may alsorequire the use of expensive four- or five-axis milling machines,special cutters (with further diameter limitations), and/or multipleset-ups to create geometry with undercuts as is typical on teeth.

AM materials can have a fairly wide range of mechanical properties. AMmaterials include suitable polymers. For a dental model geometry that istheoretically machineable, currently available AM machines may notachieve as accurate a surface as is possible by milling. Currentlyavailable AM machines are, however, able to produce much smaller concavefeatures than milling and are able to produce undercuts without furtherspecial considerations. Although AM machine generated surfaces may haveartifacts due to the layering and sometimes lateral resolution,state-of-the-art AM machines can more easily produce small curveddetails better than existing milling techniques. AM layering effects,however, can cause problems. For example, when two AM fabricatedcomponents slide against each other perpendicular to the layeringdirection, layering effects can create mechanical interlocking thatgenerates high sliding frictional forces.

In the dental models disclosed herein, excessive sliding frictionalforces are avoided by including one or more compliant features (orlocally protruding portions) as part of the shaft, the socket, or both.The compliant features are configured to accurately locate the shaft inthe socket. The compliant features are designed with dimensions andplacement to accommodate manufacturing variations in the shaft andsocket such that the components can be coupled together in all possiblecombinations of large and small sockets and shafts without generatingtoo high or too low of the associated interface forces. For example,when a shaft having a minimum dimension is coupled to a socket having amaximum dimension, there is still a suitable level of contact betweenthe compliant portions and their mating features so that the compliantfeatures will have a suitable minimum level of compression, therebygenerating a suitable minimum force between the components such that theshaft is not loose in the socket. This minimum force is sufficientlyhigh to generate a friction force sufficient to keep the shaft frommoving relative to the socket. In the tightest fit scenario, thecompliance features are configured to accommodate the increased level ofcompression without generating interface forces that are above asuitable level. The compliance features are configured to accommodatethe overall range of possible compression levels through a combinationof geometry and material properties, examples of which are describedherein.

The compliant features (or locally protruding portions) can beconfigured in a variety of ways, e.g., to include a complianceconfigured to accommodate an interference fit between the componentsdescribed herein (e.g., between a jaw component and a tooth component).In some embodiments, the compliant features (or locally protrudingportions) can have a compliance (or compression property) that allowsfor the features to compress when one component (e.g., a jaw component)is engaged with another component (e.g., a tooth component). Thiscompliance (e.g., ability to compress) can be tailored to provide adesired interference fit between the two components.

In certain aspects, the structure and/or position of the compliantfeatures (or locally protruding portions can be configured to achieve adesired interference fit. For example, locally protruding portions canbe formed on a shaft portion of a tooth component. The dimensions of theshaft can be configured to fit in a socket of a jaw component. Toachieve a desired interference fit between the components, the locallyprotruding portions can be made to have a structure that expands thelocal dimensions of the shaft such that there is an overlap between thewidth of the shaft and the width of the socket. Due at least in part tothe configured compliance (or compressive property) of the locallyprotruding portion, the shaft can be fit securely and accurately in thesocket with minimal, if any, movement between the tooth and jawcomponents. Depending on the properties (e.g., compliance) of amaterial, the locally protruding portions (or compliant features) can bemanufactured to have dimensions that correspond with a given compliancefor the material. In an example embodiment, a socket in a jaw componentmay have a width of about 5 mm. The shaft of the tooth component cansimilarly have a width of about 5 mm. Owing to, e.g., error in amanufacturing process, the shaft and socket may not fit properlytogether. Locally protruding portions (or compliant features) can beused to produce a desired interference fit between the two components.For example, a locally protruding portion on the shaft and/or the socketcan be made to increase the width of either the shaft and/or socket by apredetermined dimension. In some embodiments, the locally protrudingportion (or compliant feature) can be configured to increase the widthof the shaft or socket by 50 microns. Due at least in part to thecompliance of the locally protruding portion, the locally protrudingportion can compress and allow for a desired interference fit betweenthe two components. In some embodiments, the locally protruding portioncan be designed to increase dimensions of one component compared toanother component over a wide range. For example, a dimension (e.g.,width) of one component can be longer than a dimension of a secondcomponent over a range, such as between about 10 microns to about 100microns, between about 20 microns to about 80 microns, or from about 40microns to about 60 microns. In some embodiments, the dimension of onecomponent (e.g., a shaft of a component) can be different than anothercomponent (e.g., a socket) by a predetermined percentage. For example, awidth of a shaft at a locally protruding portion can be about 1%, orabout 2%, or about 3%, or about 4% or about 5% wider than a socketwidth. It will be generally recognized by one of ordinary skill in theart that a variety of dimensions can be manufactured and used to tailorboth compliance of the protruding portions and/or interference fitbetween the components. In certain embodiments, the compliance can betailored according to the material used to make the components and/or bythe shape or structure of the compliant feature. For example, foldedsprings can be used generate compliant features that are more compliantthan, e.g., a ridge or ball structure on a component. The spring, e.g.,can be structurally designed to compress upon application of force duein-part to the structure of the spring. The ridge or ball structure mayhave a compliance that is more dependent on the compliance properties ofthe material used to make the components. The various combinations ofcompliance for the various compliant features (or locally protrudingportions) described herein and tailored interference fit between thevarious components described herein can be predetermined according tofactor such as the properties of the materials, the dimensions of thelocally protruding portions, and/or the locations of the locallyprotruding portions.

Referring now to the drawings, in which like reference numeralsrepresent like parts throughout the several views, FIG. 1 through FIG. 4illustrate a dental model 10, in accordance with many embodiments, thatincludes a jaw component 12, a tooth component 14, and a screw 16. Thejaw component 12 defines a socket 18. The tooth component 14 has a shaftportion 20 that is received by the socket 18. A serpentine member 22(folded spring) is formed as an integral part of the jaw component 12and is disposed within the socket 18. When the shaft portion 20 ismounted in the socket 18, the presence of the shaft portion 20 deflectsthe serpentine member 22, thereby generating an interface force betweenthe serpentine member 22 and the shaft portion 20. The interface forcepushes on a face of the shaft portion 20 that is oriented such thatcomponents of the interface force act to register two faces of the shaftportion 20 against three cylindrical portions 24 of the socket 18 toprovide repeatable positioning of the shaft portion 20 lateral to theinsertion direction of the shaft portion 20. The screw 16 mates with theshaft portion 20 through a hole in the jaw component 12 to anchor theshaft portion 20 securely in the socket 18. The bottom face of the shaftportion 20 is held against the bottom face of the socket 18 (not shown)by the screw 16 to control the position of the shaft portion 20 in theinsertion direction relative to the jaw component 12.

FIG. 5 through FIG. 7 illustrate a dental model 30, in accordance withmany embodiments. Dental model 30 includes a jaw component 32, a toothcomponent 34, and a screw 16. The jaw component 32 defines a socket 38.The tooth component 14 has a shaft portion 40 that is received by thesocket 38. The dental model 30 is configured similar to the dental model10, but includes a shaft portion 40 with a generally rectangular shape.Two cantilevered springs 42 are formed as integral parts of the jawcomponent 32 and are disposed within the socket 38. When the shaftportion 40 is mounted in the socket 38, the presence of the shaftportion 40 deflects each of the cantilevered springs 42, therebygenerating an interface force between each of the cantilevered springs42 and the shaft portion 40. The interface forces push the shaft portion40 into registration with protruding cylindrical portions 44 of thesocket 38 to provide repeatable positioning of the shaft portion 40lateral to the insertion direction of the shaft portion 40. The screw 16mates with the shaft portion 40 through a hole in the jaw component 32to anchor the shaft portion 40 securely in the socket 38. The bottomface of the shaft portion 40 is held against the bottom face of thesocket 38 (not shown) by the screw 16 to control the position of theshaft portion 40 in the insertion direction relative to the jawcomponent 32. Although the screw 16 is used in the dental model 30, anysuitable type of fastener can be used.

In the dental models 10, 30, the lateral position accuracy depends onthe positional accuracy of the interfacing registration surfaces of theshaft portion and the socket. The lateral position accuracy of existingAM techniques, however, may be insufficient to produce a desired levelof positional accuracy. In general, the insertion direction for theshaft portion may not be perpendicular to the AM build layers, so it maynot be possible to ensure that side walls of the registration featuresare exactly aligned with positions that can be built by the AM device(i.e. not between steps of a stepper motor or between counts of anencoder used to position the laser or print head). In this case, betteraccuracy may be achieved by averaging the errors of opposing faces ofthe shaft or socket, a concept that can be extended from rectangularthrough polygons with more sides and also to circular, elliptical, orother shapes.

FIG. 8 and FIG. 9 illustrate a dental model 50, in accordance with manyembodiments, that makes use of the opposing compliance concept. Dentalmodel 50 includes a jaw component 52 and multiple tooth components 54.Each tooth component 54 has a generally rectangular-shaped shaft portion56 having a projection portion 58 that may be used to verify insertiondepth. The jaw component 52 defines multiple sockets 60. There are eightcompliant features 62 arranged in four opposing pairs in each of thesockets 60 with two pairs near the top of the socket 60 and two near thebottom of the socket 60. In this embodiment, the compliant features 62are protruding triangular prism portions of the jaw component 52. Thetriangular prism shape has a non-linear stiffness when compressedtowards the side walls of the socket 60 by the shaft portion 56. Ifopposing compliant features have the same dimensions, the non-linearitystrongly favors centering the shaft portion 56 between the opposingcompliant features for consistent positioning. In this embodiment, theposition in the insertion direction is controlled by pressing a lip 64at the top of the shaft portion 56 against a flat surface at the top ofthe socket 60. Friction holds each of the tooth components 54 in placewhen mounted to the jaw component 52.

FIG. 10 through FIG. 13 illustrate components of dental models that usea three-lobed “tripod” shaft 66. Each lobe interacts with a set ofcantilever springs 68 built into a socket 70. The cantilever springs canbe easily reconfigured to tune their compliance behavior, but theirrelatively small dimensions place higher requirements on the materialproperties to maintain integrity.

FIG. 14 and FIG. 15 show variations on the rectangular shaft. In theseembodiments, the compliant features are part of the shaft instead of thesocket. In FIG. 14, the compliant features are eight ribs 72 extendinglongitudinally, two on each face of the shaft. The ribs 72 have agenerally triangular cross section except that the tip is rounded. Asharp tip may be prone to breakage. In FIG. 15, the compliant featuresare two ribs 74 extending transversely around the shaft. Forlongitudinal ribs, the shaft is guided all the way in, but the frictionbuilds as the shaft is inserted and a larger area of the ribs iscompressed. If not sized correctly, or if manufacturing tolerances aretoo loose such that it cannot be sized correctly, the shaft will eitherbe loose in the socket or the friction forces will be high, makinginsertion and removal difficult. As will be discussed in regards to FIG.22, the interfacing regions of the shaft and the socket can be “stepped”to avoid overly large contact areas. The use of “stepped” interfaceregions can be applied in any suitable fashion to any suitable dentalmodel design that includes compliant features.

FIG. 16 through FIG. 18 show more embodiments that utilizerectangular-shaped shafts. In these embodiments, ribs 76 are hollowed toprovide increased compliance relative to solid ribs. In FIG. 18, a shaftportion 78 is shown seated in a socket. The socket has depressions 80 inits surface designed to mate with the ribs 76 to form a snap fit thattends to pull the shaft 78 into a detent position. In this embodiment, alip 82 at the top of the shaft portion 78 is stopped by the top of thesocket before the ribs 76 are fully engaged into the detent position sothat the lip 82 determines the final position. The lip 82 can beomitted, in which case, the position in the insertion direction would bedetermined by the balance of forces between the ribs 76 and thedepressions 80 in the socket.

FIG. 19 and FIG. 20 show another embodiment similar to those in FIG. 16through FIG. 18 except that the ribs are not hollowed and a snap fit isgenerated by separate hooks 84 near the bottom of the shaft that engagewith a sloped opening 86 at the bottom of the socket. In manyembodiments, the slope of the hook surface and of the mating surface onthe socket is configured so that the snap fit is not permanent and thedie can be removed easily. It is also possible to configure the slope ofthe hook surface and of the mating surface on the socket so that the diecan only be removed by manipulating a feature on the hook 84 todisengage the hook 84 from the socket. In this embodiment, the positionin the insertion direction is determined by the interaction of shouldersurfaces 86 near the bottom of the shaft and mating socket surfaces nearthe bottom of the socket.

FIG. 21 and FIG. 22 show another embodiment that can be used, forexample, for crowns and bridges. In this embodiment, the complianceportion is a set of spherical features 88 on the shaft. The sphericalshape has a non-linear stiffness with the advantages discussed above forFIG. 8 and FIG. 9. The compliance is easily manipulated by choosing theradius and amount of overlap of the spherical feature 88 with the bodyof the shaft. Other suitable shapes can also be used. For example, anellipsoid can be used with the narrow equators against the socket wallsto increase the compliance for a given overall size. As shown, eachsphere 88 contacts the socket at two points on adjacent faces of thesocket. Alternate embodiments can be configured such that only one pointon each sphere 88 makes contact with an adjacent face of the socket. Forexample, each of the longitudinal ribs in FIG. 14 can be replaced by twospheres, one near the top of the shaft and one near the bottom.

The number of contacts can be reduced, for example, until there are onlysix contact points, which define a kinematic mount. The addition of asuitably placed seventh contact can create an opposing force on theother contact points, so that the shaft is firmly positioned in thesocket, rather than being dependent on an outside force, typicallygravity, to ensure that all the contacts remain touching. In practice,because of resolution limitations associated with AM fabrication of asingle surface, it may be preferable to use a greater number of opposedcontacts to average out the position error of the surfaces.

While most of the embodiments described herein use a rectangular shaft,any other suitable shape, for example a triangular shaft, can also beused. The shaft shape employed can be somewhat independent of the numberof contacts. For example, instead of using four contact spheres near thebottom of the shaft and four near the top, three near the bottom andthree near the top can be used with each sphere having two points ofcontact with adjacent faces of the socket. A shaft of any suitable shape(e.g., triangular, rectangular, pentagon, etc.) can be used to connectthe spheres.

Note that the hole through the shaft shown in FIG. 21 and FIG. 22 is forprototyping purposes and can be omitted. In these figures, a rectangularprism 90 represents the portion that would have the shape of thepreparation. As shown in FIG. 22, the socket has walls 92 parallel tothe insertion direction, but the walls 92 are stepped so that the lowerset of compliance portions are loose in the socket until they reach thestep near the bottom of the socket. This keeps the insertion force nearzero until the shaft is almost fully inserted into the socket. Aprojection 94 at the bottom of the shaft extends through a hole in thejaw component and is positioned and shaped such that its end surface isflush with the bottom of the jaw component. This enables easy checkingthat the shaft is fully inserted into the socket as any error would beapparent by the unevenness of the projection 94 relative to the bottomof the jaw component. Note that for the contact that sets the positionin the insertion direction, high compliance is undesirable unless thereare two opposing compliant contacts, as can be provided in an embodimentsimilar to the embodiment of FIG. 18 but without the lip. For a singlecontact, a hard stop in the insertion direction provides forwell-defined and repeatable positioning.

Most of the embodiments described herein have the compliant features onthe shaft. Nearly all of the described embodiments, however, can bereconfigured to place the compliant features on the socket instead.Additional embodiments can use a mixture of locations for the compliantfeatures with some on the shaft and some on the socket. For AMtechniques using a solid support material, such as Objet, it may bepreferable to put the compliant features on the shaft in order to avoidsmall concave features from which the support material is difficult toremove, assuming that the shaft is the generally convex and the socketconcave as in many embodiments. For other AM techniques, otherconsiderations may guide the choice of where to locate the compliantfeatures.

FIG. 23 shows an improved embodiment of the embodiment of FIG. 21 andFIG. 22 and also illustrates a realistic preparation shape 96 and agenerally conical transition 98 from the visible surface to the shaft.In this improved embodiment, ribs 100 have been added between thespherical compliance features to stiffen and strengthen the shaft.Additional material can also be added to any other suitable location ofthe shaft, for example, all locations of the shaft except immediatelyadjacent to the upper and lower spheres 88. The ribs 100 are configuredto not contact the socket.

Although not shown in many of the embodiments illustrated herein, it maybe preferable to configure the contact points such that the die can onlybe inserted in one orientation. A keying feature can also be used toprevent incorrect orientations.

Implant analog components typically provide mounting features for anabutment that is used to create a crown. The loads on such mountingfeatures can be relatively high making it preferable that the analog bemetal. When the analog is metal, cost considerations and materialproperties may make it preferable to put compliance features in thesocket instead of on the analog.

FIG. 24 through FIG. 26 illustrate two implant analog embodiments 102,104. Each has a single tab feature 106 configured to mate with acorresponding slot in the socket providing a hard stop in the insertiondirection and defining the angular position of the analog around theinsertion direction. In FIG. 24, a handle 108 is provided for easyremoval of the analog 102. In FIG. 26, a tapped hole 110 allows a screwto be used as a temporary handle to remove the analog 104.

FIG. 27 and FIG. 28 show a socket 112 with multiple compliance portions114. FIG. 31 shows an implant analog 116 mounted in the socket. FIG. 29and FIG. 30 show similar embodiments, but without the socket compliancefeatures, and show the top surface of the tab 106 on the analog incontact with the socket to limit the insertion depth. FIG. 32 shows asimilar analog mounted in a socket with compliance features. Thisversion adds a screw 118 passing through the analog's tab to provide afirm mounting. The screw 118 prevents inadvertent movement of the analogwhen an abutment is being mounted on the analog or when a crown is beingmounted on the abutment.

FIG. 33 and FIG. 34 illustrate an embodiment that includes an implantanalog 120 and a socket 122 and uses transverse ribs 124 in the socketas the compliant portions. Similar to the embodiment illustrated in FIG.22, the compliant portions are “stepped” so that the analog 120 can beinserted with almost no force until it is almost seated. The analog 120has a flat surface 126 that interfaces with a protruding portion 128 ofthe socket 122 to prevent rotation about the insertion direction. A hole130 in the bottom of the socket allows a screw to be used to firmlymount the analog 120 in the socket 122. Alternatively, the analog caninclude a projection, similar to the projection of the embodiment ofFIG. 22, that is used to verify the correct insertion depth. When aprojection is used, it may be easier and less expensive for theprojection's end surface to be perpendicular to the insertion directionand modify the bottom of the jaw model to have a face parallel and flushwith that end surface for comparison, rather than having the jaw modelbottom be flat and having to cut a custom angle on the analogappropriate for the angle at which the socket is oriented in the jawmodel.

Other variations are within the spirit of the present invention. Thus,while the invention is susceptible to various modifications andalternative constructions, certain illustrated embodiments thereof areshown in the drawings and have been described above in detail. It shouldbe understood, however, that there is no intention to limit theinvention to the specific form or forms disclosed, but on the contrary,the intention is to cover all modifications, alternative constructions,and equivalents falling within the spirit and scope of the invention, asdefined in the appended claims.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. The term “connected” is to beconstrued as partly or wholly contained within, attached to, or joinedtogether, even if there is something intervening. Recitation of rangesof values herein are merely intended to serve as a shorthand method ofreferring individually to each separate value falling within the range,unless otherwise indicated herein, and each separate value isincorporated into the specification as if it were individually recitedherein. All methods described herein can be performed in any suitableorder unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate embodiments of the invention and does not pose a limitationon the scope of the invention unless otherwise claimed. No language inthe specification should be construed as indicating any non-claimedelement as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

What is claimed is:
 1. A method of designing a dental model comprising:digitally generating a jaw component designed to represent a portion ofa patient's jaw and defining a socket extending though the jawcomponent; digitally generating at least one dental structure componentto be demountably attachable to the jaw component, the at least onedental structure component designed to have a first plurality ofmaterial layers and representing at least one dental structure in theportion of the patient's jaw and; digitally generating on the at leastone dental structure component, a shaft shaped to be inserted into thesocket of the jaw component along an insertion direction, the shafthaving a projection portion, the projection portion protruding distallyfrom a planar distal end of the shaft and wherein the projection portioncomprises a distal surface that aligns with a distal external surface ofthe jaw component adjacent to the socket to allow for verification ofinsertion depth and that the at least one dental structure component isproperly positioned along the insertion direction for the at least onedental structure component; and digitally generating a plurality oflocally protruding portions on the shaft and extending along theinsertion direction of the shaft so as to form an interface between theat least one dental structure component and the jaw component when theat least one dental structure component is inserted into the socket ofthe jaw component.
 2. The method of claim 1, wherein the orientation ofthe first plurality of material layers are not perpendicular to theinsertion direction.
 3. The method of claim 1, wherein the jaw componentcomprises a second plurality of material layers configured to representthe portion of the patient's jaw and defining the socket.
 4. The methodof claim 3, wherein the orientation of the second plurality of materiallayers are not perpendicular to the insertion direction.
 5. The methodof claim 1, further comprising fabricating the at least one dentalstructure component.
 6. The method of claim 1, wherein the plurality oflocally protruding portions form a friction fit between the at least onedental structure component and the jaw component when the at least onedental structure component is inserted into the socket of the jawcomponent.
 7. The method of claim 6, wherein the plurality of locallyprotruding portions comprise ribs.
 8. The method of claim 7, wherein theribs comprise a generally triangular cross-section with a rounded tip.9. The method of claim 1, wherein the shaft comprises a three-lobedgeometry.
 10. The method of claim 1, wherein the socket comprises arecess corresponding to the projection portion, and wherein the recessis configured to receive and provide a friction fit with the projectionportion of the shaft.
 11. The method of claim 1, wherein the socketcomprises a recess corresponding to the projection portion, and whereinthe recess is configured to receive the projection portion and limitinsertion depth of the projection portion.
 12. The method of claim 1,wherein the shaft comprises a rectangular geometry.
 13. The method ofclaim 1, wherein the projection portion comprises a rectangulargeometry.
 14. The method of claim 1, wherein the plurality of locallyprotruding portions are compressible.
 15. The method of claim 14,wherein friction between the at least one dental structure component andthe jaw component is configured to build as the plurality of locallyprotruding portions are progressively compressed during insertion of theat least one dental structure component into the socket of the jawcomponent.
 16. The method of claim 1, wherein the socket comprises arecess corresponding to the projection portion, and wherein the recesscomprises a mating surface configured be flush with the distal surfaceof the projection portion when the shaft is fully inserted into thesocket.
 17. The method of claim 1, further comprising digitallygenerating a plurality of protrusions disposed at varying depths along alength of the socket, the plurality of protrusions configured to providetactile feedback at the varying depths when the shaft is inserted intothe socket.
 18. A method of designing a dental model comprising:generating a jaw component designed to represent a portion of apatient's jaw and defining a socket; digitally generating at least onedental structure component to be demountably attachable to the jawcomponent, the at least one dental structure component designed to havea first plurality of material layers and representing at least onedental structure in the portion of the patient's jaw; digitallygenerating on the at least one dental structure component, a shaftshaped to be inserted into the socket of the jaw component along aninsertion direction; and digitally generating a projection portion, theprojection portion protruding distally from a planar distal end of theshaft and wherein the projection portion extends along the insertiondirection of the shaft so as to allow for verification of insertiondepth and provide a friction fit between the at least one dentalstructure component and the jaw component when the at least one dentalstructure component is inserted into the socket of the jaw component.19. The method of claim 18, wherein the orientation of the firstplurality of material layers are not perpendicular to the insertiondirection.
 20. The method of claim 18, wherein the jaw componentcomprises a second plurality of material layers configured to representthe portion of the patient's jaw and defining the socket.
 21. The methodof claim 20, wherein the orientation of the second plurality of materiallayers are not perpendicular to the insertion direction.
 22. The methodof claim 20, further comprising fabricating the at least one dentalstructure component.
 23. The method of claim 18, further comprisingdigitally generating a plurality of protrusions disposed at varyingdepths along a length of the socket, the plurality of protrusionsconfigured to provide tactile feedback at the varying depths when theshaft is inserted into the socket.